Scientists in the Netherlands have assessed how the so-called blue-green roofs can help reduce the operating temperature of rooftop PV panels and have found they provide a significant cooling effect. The irrigation system used for the research project relies on an additional water supply sourced from grey water from showers that is transformed into irrigation water.
Having a monolithic dome house I am actually curious how setting up vegetation across the dome would work. The shell is a 2 foot layer of concrete throughout it.